Capacitor containing aluminum anode foil anodized in low water content glycerine-phosphate electrolyte

A capacitor prepared by the process

• fabricating an aluminum plate;
• pre-hydrating said aluminium plate;
• contacting said plate with an anodizing solution comprising glycerine, about 0.1 to about 2.0%, by weight, water and about 0.01 to about 0.5%, by weight, orthophosphate;
• applying a voltage to said aluminum plate of at least about 220 volts.

A capacitor prepared by the process of

• fabricating an aluminum plate;
• pre-hydrating said aluminium plate;
• contacting said plate with an anodizing solution comprising glycerine, about 0.1 to about 2.0%, by weight, water and about 0.01 to about 0.5%, by weight, orthophosphate;
• applying a voltage to said aluminum plate and determining an initial current;
• maintaining said first voltage until a first measured current is no more than 50% of said initial current;
• increasing said voltage and redetermining said initial current;
• maintaining said increased voltage until a second measured current is no more than about 50% of said redetermined initial current, and
• continuing said increasing said voltage and said maintaining said increased voltage until a final voltage is achieved.

A capacitor comprising:

• an etched aluminum anode and a dielectric layer comprising phosphate doped aluminum oxide;
• prepared by the process of:
• forming an aluminum plate;
• pre-hydrating said aluminium plate;
• contacting said plate with an anodizing solution comprising glycerine, about 0.1 to about 2.0%, by weight, water and about 0.01 to about 0.5%, by weight, orthophosphate;
• applying a voltage to said aluminum plate and determining an initial current;
• maintaining said first voltage until a first measured current is no more than about 50% of said initial current;
• increasing said voltage and redetermining said initial current;
• maintaining said increased voltage until a second measured current is no more than 50% of said redetermined initial current, and
• continuing said increasing said voltage and said maintaining said increased voltage until a final voltage is achieved.